The Broadcom 440x 10/100 integrated controller is for the LAN (hard wire) connection. You have to download and install wireless drivers to get the connection. I have included the link to download the drivers. http://support.dell.com/support/downloads/index.aspx?c=us&cs=19&l=en&s=dhs
Please select Drivers & Downloads - Enter your Service tag or select the system model to get the compatible drivers. You will find the wireless drivers under network controller drivers.
Hope this answers your concern, if you have any issues you can reach our tech support over the phone, or reach out to us at @dellcares on twitter or facebook.com/dell. We will be glad to help.